Intelligent reflecting surfaces (IRSs) can be beneficial to both information and energy transfer, due to the gains achieved by their multiple elements. In this work, we deal with the impact of spatial correlation between the IRS elements, in the context of simultaneous wireless information and power transfer. The performance is evaluated in terms of the average harvested energy and the outage probability for random and equal phase shifts. Closed-form analytical expressions for both metrics under spatial correlation are derived. Moreover, the optimal case is considered when the elements are uncorrelated and fully correlated. In the uncorrelated case, random and equal phase shifts provide the same performance. However, the performance of correlated elements attains significant gains when there are equal phase shifts. Finally, we show that correlation is always beneficial to energy transfer, whereas it is a degrading factor for information transfer under random and optimal configurations.

中文翻译：

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空间相关下具有智能反射面的 SWIPT


智能反射表面（IRS）由于其多个元件所实现的增益而有利于信息和能量传输。在这项工作中，我们在同时无线信息和电力传输的背景下处理 IRS 元素之间空间相关性的影响。性能根据平均收获能量以及随机和相等相移的中断概率进行评估。推导了空间相关性下这两个指标的封闭式解析表达式。此外，当元素不相关和完全相关时，会考虑最佳情况。在不相关的情况下，随机和相等的相移提供相同的性能。然而，当相移相等时，相关元件的性能会获得显着的提高。最后，我们表明相关性总是有利于能量传输，而在随机和最优配置下它是信息传输的退化因素。